class BackgroundStart extends egret.Sprite{
	public cover:egret.Shape;//遮盖
	public constructor() {
		super();
		 this.addEventListener(egret.Event.ADDED_TO_STAGE,this.init,this);
	};
	private init() {
		// 遮盖层
		this.cover= new egret.Shape();
        this.cover.graphics.beginFill( 0x000000, 0.5);
        this.cover.graphics.drawRect( 0, 0, this.stage.stageWidth, this.stage.stageHeight );
        this.cover.graphics.endFill();
        this.addChild( this.cover );
	};
}